Stupidity: When Charley goes to Evil's house, he asks him how to protect himself from vampires. Since Charley is such a huge fan of Fright Night and watches it all the time, he should already know everything to protect himself from Jerry.
Stupidity: Bobby didn't need to jump out of the way when the truck was coming towards him on the road. He was already dead, and the truck would have just gone through him (like he tried to convince Lenny). Bobby walked through walls, so why wouldn't he assume the truck would just pass through him?
Stupidity: No high school is just going to let a new kid in the way the "male" Terri got in. In reality, there would be some kind of background records and registering involved of some kind. If just walking around the campus at random, that would be one thing - but registered in actual classes the way he/she did would not just happen the way it looked in the film.
Suggested correction: Being a fan of horror films in general and watching Fright Night on TV doesn't necessarily give someone expert knowledge of how to fight vampires. In fact, not every vampire movie is consistent with rules (including this one) and it is far from stupid to consult a friend who knows more than you about the subject. Think about it like this: If you watched every comic book movie that was made and every TV show based on comic books, then found out Galactus was real and you had to fight him, you wouldn't ask your friend who was a comic nerd for advice?
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